When you go to the dentist, you want to know that he is focused on your teeth, not on his attractive young assistant. But in our next story, one dentist says he was so distracted by her beauty and the temptation she brought to his marriage that he fired her. And a court backed him up. Here's paula faris. Reporter: Well, the cat's out of the bag. The beautiful get all the breaks. The pretty get all the perks. And the gorgeous get all the gigs. Look at the waitresses. Yeah? Reporter: It really ticked off elaine in this classic "seinfeld" episode when she thought this diner would only hire well-endowed waitresses. You know what? That's discriminatory. Reporter: Turns out, it wasn't lookism -- it was nepotism. They are my daughters. Oh! Reporter: It wasn't so funny more recently, when teen clothing retailer abercrombie and fitch ceo mike jeff riches caused a plus-sized controversy over comments that they only go after the attractive, all-american kid. And that's why they hire good-looking people in their stores. Amid plummeting sales, abercrombie had to back track. But beauty bias can cut both ways. I'm melissa nelson. I was fired because my boss thought I was too attractive. Reporter: Which brings us to ft. Dodge, eiowa, and their fields of opportunities. America's heartland, for some twisted matters of the heart. All she ever wanted to do was be a dental assistant. Reporter: Steve is melissa's high school sweetheart. They are married with two young children. She wanted to work for dr. Knight's office, so she job shadowed there. She got a job there and just everything fell into place. She loved her job. Reporter:33-year-old melissa was the dental assistant for dr. James knight. By the dentist's side, eight hours a day for a decade. It was a fun working environment. Reporter: How did you view dr. Knight? I viewed him as a father figure. As a -- as a dad. Reporter: He was your mentor, right? Very much so. Reporter: How close did the two of you get? When we had both of our kids, his family came and visited in the hospital. Reporter: Melissa says it was all a gas, until the doc started pulling more than teeth. Once he hit 50, she says, he was working out -- pumping iron and getting buff. He became more confident and more outgoing. Reporter: Do you think he was going through a mid-life crisis? That's the only thing I could come up with. Reporter: The two had a friendly relationship. Trading personal text messages during off-hours. But then, melissa says, it went from cordial to creepy. He would ask me about my personal life. He would ask me how often i would have sex. Reporter: And melissa says when she answered and implied not that often, the dentist offered this artful analogy. "That's like having a lamborghini in the garage and never driving it." And he warned his mentee -- "if you see my pants bulging, you'll know your clothes are too revealing." Reporter: This was melissa's standard issue scrub suit uniform and occasionally, on humid days her lab coat was removed -- revealing her 5'1" frame and a simple crew neck t-shirt. Oh, my god. I'm sorry. I'm a squirter, dale. Reporter: It seemed to us strikingly similar to this scene from the movie, "horrible bosses." Stop it. Shalom. Someone is circumcised. Reporter: Did you flirt with him? No. Reporter: So there's no attraction. Absolutely not. Reporter: Did you do anything to lead him on? Never. Reporter: You must've done something. I don't know what. I showed up for work everyday. Reporter: Melissa says she brushed off her boss's comments for six months, hoping they would stop. But things came to a head when there was an exchange during non-business hours. The dentist's wife caught them texting each other while he was on vacation -- and made sure it would end. His wife came in with a purple folder, and just sat it on his desk and walked out without saying anything. Reporter: Thus began a day at this dentist's office with more discomfort than a string of scheduled root canals. Talk about intervention. Dr. Knight even brought in his local pastor. I found out later that it was his minister from church. Reporter: It's his pastor, it's you and it's your boss. Yes. The three of us sitting in -- in the office. Reporter: Did you think, "what the heck is going on?" Absolutely. I had no idea why I was in there. Reporter: And in that purple folder? A pink slip. Dr. Knight said I couldn't work in the office, because he was becoming attracted to me, and not able to focus on his family and his family life. Reporter: What was your reaction to this? He can't control himself? I instantly broke down in tears. All I remember is just sitting there and not able to get up, telling him that I love my job. Reporter: Melissa's husband rushed to the dentist's office. I said, "what's going on? Is there a mistake?" He said, "i've got feelings for your wife and it's affecting my family." And he felt the best option to save his marriage was to terminate missy. He saw her as a threat. He told me several times that, he said, "i want you to know, steve, that your wife has done nothing wrong." Reporter: When he said he didn't feel like he could control himself, and that an affair might start down the road, what was your reaction? I'm like, that's absurd. Why would those thoughts even cross his mind? This is my wife. Why is he thinking of her as an object? And it infuriated me. Reporter: And the news also infuriated some in this close-knit reserved town of 25,000 people. We met ruth and jerry hancock at the local malt shop, netties. I have just never, ever seen her do anything inappropriate myself. Then all of a sudden we find this attraction as being a reason, to let her go. I don't think that's justified. Reporter: After the firing, they found a new dentist. Now, dr. Knight offered melissa a month's severance for ten years of stellar work. But melissa vowed to fight tooth and nail. The good news for the court is this might be the easiest case that you have all year. Reporter: When we come back, how melissa decided to retaliate in a court of law. This was a woman who did nothing to get herself fired, except, you know, bring her breasts to work. Reporter: The dentist's surprising defense. And as an orthodontist might say, brace yourself. Because you may not believe where else she took her case.

This transcript has been automatically generated and may not be 100% accurate.

Now Playing: Real Estate Agent Barely Escapes With Life After Attack by Client

Now Playing: Caught on Camera: Tree-Cutting Fails and Mishaps

Now Playing: Having an Open House? Protect Your Stuff

Now Playing: Tree-Cutting Fails: When Trees Are Cut the Wrong Way

Now Playing: Woman Harasses Couple After Losing Bid on Dream Home

Now Playing: {{itm.title}}

{"id":19859976,"title":"Melissa Nelson: Too Hot to Work","duration":"6:58","description":"Part 1: Dr. James Knight fired Nelson because he felt his attraction to her threatened his marriage.","url":"/2020/video/melissa-nelson-hot-work-19859976","section":"2020","mediaType":"Default"}